Simplify common recipes

[ryanb]

So many recipes start with gathering a tree to make charcoal to smelt something. This makes more advanced recipes look more complex than they need to.

Most people know how to smelt iron, and have charcoal lying around. If an object is used as a part of other recipes, consider breaking it there and turning it into an ingredient. In the case they don’t know how to make that item they can expand the recipe to add it.

The “used in other recipes” condition will take some work. I think there should be a “commonality” variable for each object which is dependent on how many other objects are made from it. Then look for “spikes” in the recipe chain as a sign to break it there.